Dies for punching small metal parts



V. PUG

DIES FOR PVUNCHING SMALL METAL PARTS. APPLICATION FILED FEB. 4. 1920.

1,415,477, Patented May 9,1922,

voJrncH rue, or PRAGUE-vINomAn BOHE I'AJ- DIES. roaruncn me SMALL METAL mars.

Application filed .Eebruary 4, 1920. Serial No.35 6,115.

To whom it may concern:

Be 1t known that "I, VoJ'rnoH PUG, a citizen of the Republic ofCzecho-Sloyakia, residing chines for making small metal parts or articles, in which a strip or ribbon of metal is advanced step by step between formingor B drawing dies which by successive operations give shape to the articles and then separate them from the strip. In such machines it is of prime importance that the step by-step movement, of the strip shall be performed with absolute regularity or accuracy in order that the dies may properly operate on the partially formed articles and inorder'that they may be properly separated from the strip. According to my invention, I provide improved devices for obtaining regularity or accuracy in the feed or advance of the metal between the dies, and while my improvements are especially designed for use in connection with a machine for making metalbuttons I wish it understood that they may be used in machines of. other kindsfor producing other articles. a i In the drawings Figure 1 shows a longitudinal section of so much of a machine for making small metal parts or articles .as is necessary to illustrate my improvements. 5

Figure 2 shows a section through the punches on the line 2-2 of Figure 1. Figure 3 shows a longitudinal section of the delivery end of the -machine, showing some of the parts in different positions from those shown in Figure 1. Figure 4 is a section on the line 4l4 of Figure 2 and shows an elevation of the delivery end of themachine.

The machine illustrated is designed to form small metal parts or articlesztm. a

metal strip or ribbon X by means ofupper and lower dies A andB which-have a clear space Y between them through which the strip or ribbon of metal isadvanced'stepby-step in any suitable way, as by rollers C I and D which maybe actuated intermittently in any suitable or well-known way.

The lower dies are formed in a metal bar strip.

or block and are in the form shaped recesses or matrices.

the matrices 1n the lower die. The bars A and B Specification of Letters Patent. .Pate t' d M 9 1922 I The upper die comprises a metal bar 01: lolock havlng vertical openings {through it ;1n which punches operate above are held a suitable distance apart bylon-' gltudinally arranged strips of metal E to provide the clear space Y forthe passage oi the metal strip orribbonzX. The-parts A,

and E are secured together by screwse. The punches andmatrices are so formed, as is usual, to gradually: press or draw the metal into suitable shape. to small metal articles desired. I v .As the manner in which the'parts or articles are [produced v.forms no part of my are illustrated.

it from the strip and forms'holes to inth'e' It is not strip between the. dies by.-ordi'nary feed rollers with suflicient regularity unless some Special means be provided for ensuring .ac-

curacy and various devices have, heretofore been employed for this purpose. Myv improvements consist in novel and highly of ficientdevices for accomplishing thedesired result. i

produce the i present invention,:only a few of the punchesv possible. to advance the: metal At the deliveryend of the machine the t bar A is .formedlwith a recess or chambera its inner end, presses against the head g of the pin and at its rear end it presses against a plate J. which closes the hole hand is de- "into which projects a pin G having a headed bore is arranged a coiled spring 2'. which, at

tachably secured to the bar A, by screws 7:. I

:A'plate L is arranged .to slide to a limited extent in. a recess m above the recess a, which former recess is closed at its rear endv by the plate J, above referredto, The

front end of the plateL "is recessed, as most clearly shown in Figure 2, so that this end of the plate may partially surround, the punch 2. The plateL- is formed with a recess Z through which the shank of ascrew M extends,- said screw beingattachedv to the bar A inthemanner clearly indicated The head of the screw M operates in a r cess m in the plate L. When the screw is tightened the plate is held firmly in position in the bar A. By loosening the screw the plate may be adjusted to a limited eX- tent longitudinally of the bar andthen held in its adjusted position. The plate L carries a pawl or pivoted finger N, the upper end of which is pivoted at a to the plate L and the lower end of which extends into the space Y to a small extent beyond the inner or lower face of the bar A. This pawl or finger is engaged by the spring-pressed pin -Gr, which latter operates to press the pawl or finger forwards, the forward movement of the finger being limited by the front wall of the recess a, as clearly indicated in Figure 1. The rearward movement of the pawl is limited by the shoulder a of the plate L, in the manner indicated by dotted lines in Figure 1.

By removing the plate J and the screw M the plate L and the pawl connected therewith may be detached from the dies for purposes of repair or replacement and the headed pin G and the spring 71 may be also removed and replaced if desired.

In the operation of the machine the metal strip or ribbon X is moved between upper and lower dies by the feed rolls C and D which are operated intermittently. At each step the punches descend and press the metal strip against the lower die and-give shape to the blanks in the strip. When the dies have descended to their full extent the metal strip will lie in the position shown in Figure 3, which figure also shows how one completed article is separated from the strip and in this way a hole is made in the strip. Figure 3 shows a series of holes w thus formed in the strip. When the punches rise they will carry with them the metal strip inasmuch as the metal adheres to the punches. It will of course be understood that when the punches thus rise with the strip they engage properly the blanks in the strip which are properly spaced. As the strip rises and when the pawl or pivoted finger N is in the position shown in Fig. 1 and also in Fig. 2, said finger will enter a hole w in the strip immediately below it, so that it will engage the strip in the manner indicated in Figure 1, which is the feeding position of the strip. If, now, the .feed rolls be actuated to advance the strip, the strip will move only to an extent limited bythe movement of the pawl; that is, until the pawl strikes the shoulder a of the plate L, in the manner indicated by dotted lines in Figure .1. This position ofthe strip is maintained until the punches again descend, engage the metal strip at the proper places, and continue the operation infthe usual way.

"While the metal strip is being pressed downwardsby the punches, the spring finger is.

disengaged from the strip and; is moved forward to engaging position by the springpressed pin G. After this the operations are repeated indefinitely.

As is well understood, the metal strip or ribbon is usually .of great or indefinite length and is taken from a reel. When commencing the operation the front portion of the strip is passed through the machine by hand with sufficient care to properly form a series of blanks. After the proper number of blanks have been formed and one or more holes to are produced in the strip to receive the pawl N, the entire operation may be performed automatically.

I claim as my invention 2- 1. In a machine for forming small metal parts or articles from a strip of metal, the combination with means for punching the strip, for raising and lowering it and for advancing it stepby-step, of a pivotally mounted finger adapted to engage the strip when raised and to be moved thereby, and means for limiting the movement of said finger.

2. In a machine for forming small metal parts or articles from a strip of metal, the combination with means for raising and lowering the strip, for punching the strip and for advancing it step by step, of a spring-pressed finger adapted to engage the strip, when raised and to be moved thereby, and means for limiting the movement of saidfinger.

3. In a machine for forming small metal parts or articles from a strip of metal, the combination with means for punching the strip, for raising and lowering the strip and for advancing it step by step, of a pivoted spring-pressed finger adapted to engage the strip and to be moved thereby whenraised,

and means for limiting the movement of.

said finger.

4. In a machine for forming small metal parts or articles from a'strip of metal, the combination with means for punching the strip, for raising and lowering it and for advancing it step by step, of a pivotally mounted finger adapted to engage the strip, means for limiting the movement of said finger, and means for shifting the pivot of the finger in a direction parallel with the advance movement of the strip.

5. In a machine for forming small metal parts or articles from a strip of metal, the combination with upper and lower dies with a space between them for the passage ofthe strip, of means for raising the strip from the lower die through the space to the up per die and for lowering the strip from the upper die to the lower die, means for advancing the strip step by step, a finger projecting into said space and adapted to engage the strip when raised, and to bemoved thereby and means forlimiting the movement of the finger. v

6. In a machine for forming small metal parts orarticles from a strip of metal, the combination with upper and lower dies with a space between them for the passage of the strip, of means for raising and lowering the strip between the dies, means for advancing the strip step by step, a pivotally mounted spring-pressed finger which projects into said space and is adapted to engage the strip and to be moved thereby, and means for adjusting the position of thefinger longitudinally of the strip.

7. In a machine for forming small metal parts or articles from a strip of metal and for detaching them therefrom, the combination with upper and lower dies which give shape to the articles and detach the completed articles from the strip and which have a clear space between them for the passage of the strip, means for advancing the strip step by step in said space, a pivoted springpressed finger depending from the upper die and adapted to extend into a hole out in the strip by the operation of the dies and to be moved thereby, and, means for limiting the movement of the finger while advancing with the strip. Y

pressed finger depending from the upper die and adapted to extend into a hole cut in the strip by the operation of the dies and to be moved thereby, means for limiting the a pivoted springmovement of the finger while advancing with the strip,

and means for limiting the 1 movement of the finger when returned by the spring. I

In testimony whereof, I have hereunto subscribed my name.

voJTnoH Poo. 

